As integrated circuit packages grow smaller, it becomes more and more difficult to find sufficient physical room to mount the required number of input and output pins. Two very common functions that require a large number of pins are outputs to drive displays and inputs from keyboards. A typical prior art design might have sixteen pins, each of which is dedicated to a particular display element such as a light emitting diode. Another group of dedicated pins serves to input signals from a keyboard. My invention contemplates a way to combine these two functions on one set of shared pins.